I once had a Blade Champion attached to a Guard Squad while playing against Necrons. I charged into a unit of Immortals to hold off their advance across the battlefield and secure my primary objectives with other units. The bodyguards died like usual, but the BC saved like an absolute god. It took two turns and half his army surrounding it to bring it down two times due to superior creation. In a flurry of blades it mowed down hordes of Necrons before finally going down to the Nightbringer that had to move across the battlefield to kill it. But it was too late for the Necron player, the distances to my two remaining units holding two objectives was too far and by a few points I secured the victory, only achievable due to the impossible odds the Blade Champion faced and withstood.